The landing of helicopters on board ships requires handling means to move such aircraft between a landing area on the deck of a ship and a storage area or hangar. Generally, aircraft will land in the landing area but their orientation with respect to the entrance to the hangar is variable and cannot be predicted. It is necessary therefore to align the helicopter with the hangar entrance prior to moving the helicopter into the hangar. It will be appreciated that in adverse weather and/or sea conditions such movement of aircraft may be extremely hazardous and a handling system should be able to handle aircraft in a manner ensuring the safety of the helicopter and the ship's crew.
Existing systems utilise handling trucks or arrangements of pulleys, winches and cables on the landing deck of ships. Such systems, however, are undesirable because the presence of apparatus above the deck surface creates potentially dangerous obstacles to landing aircraft and the ship's crew. European Patent Application 518405 (Riva Calzoni S.p.A) relates to a device for gripping, handling and transporting helicopters on board ships. The document discloses the use of longitudinal and transverse guide rails and gripping beams which are stored on deck and run along the transverse guides to engage the helicopter. In order to effect transverse movement of an aircraft, the aircraft has to be lifted from the deck. Such a lifting arrangement imposes undesirable strain on the support mechanism and can affect the stability of the aircraft. U.S. Pat. No. 5,570,858 to Craig, the disclosure of which is incorporated herein by reference, describes an aircraft restraining system for securing and handling an aircraft on the deck of a ship. The system includes two restraining beams which are transversely movable for engaging the aircraft. When not in use, the beams lie in recesses in the surface of the deck and thus they are constantly exposed to sea-water and the like. Exposure of the beams to such conditions increases their susceptibility to corrosion and increases maintenance requirements.
It is an object of the present invention to avoid or minimize one or more of the foregoing disadvantages.